Analysis of the backscatter spectrum in an ionospheric modification experiment

Abstract

The purpose of this study is to compare predictions of the backscatter spectrum, including effects of ionospheric inhomogeneity, with experimental observations of incoherent backscatter from an artificially heated region. Our calculations show that the strongest backscatter echo received is not from the reflection level, but from a region some distance below (about 900 m for an experiment carried out at Arecibo).By taking the standing wave pattern of the pump into account properly, the present theory explains certain asymmetrical features of the upshifted and down-shifted plasma lines in the backscatter spectrum, and the several satellite peaks typically accompanying them.

Scattering of Electromagnetic Waves on Enhanced Fluctuations in Bounded Plasmas

“…[ 151, where, however, the wavevector of the pump field is zero). It should also be stressed that the present problem with sharp density discontinuities (including both incident, reflected, refracted and incoherently scattered waves) obviously is very different from the theory of slightly non-uniform plasmas or plasmas with linear density gradients (see, e.g., [7,16,17]) and that the coupling of the sideband modes U + with the pump wave w o in order t o produce weak radiation at the fluctuation frequency w has been neglected. In conclusion we believe, however, that stimulated scattering from bounded plasmas will be of interest for experiments in the laboratory and then also for ionospheric experiments.…”

Mathematical models for water vapour resistance prediction of printed garments

“…The rate of sweat evaporation largely depends on the garment that represents a barrier in this process. Essentially, a garment disrupts sweat evaporation from the skin surface, and this insufficient evaporation often provides the feel of discomfort found while wearing a garment [26]. The evaporation rate itself affects comfort that is received through wearing of a certain garment.…”